Having an epidural: is it painful and what are the side effects?

Having an epidural is an injection into the back, which is given to women during childbirth. One of the most effective types of pain relief in labour, it can only be given by an anaesthetist in a hospital

a woman in hospital having an epidural for pregnancy
(Image credit: Getty Images)

Having an epidural is an injection into the back, which is given to women during childbirth. One of the most effective types of pain relief in labour, it can only be given by an anaesthetist, when you choose to give birth in a hospital.

It goes into the "epidural space" in your spine and will usually numb all sensation, from the waist down. According to research by the UK's Care Quality Commission, around 30% of women opt for an epidural for pregnancy. We talked to Consultant Obstetric Anaesthetist Dr Simon Jones to find out all you need to know about epidural side effects and how they work. He told us, "There are lots of myths about epidurals and their effects. Most of those have been disproven. We know epidurals are very safe, for you and your baby. Epidurals are also the most effective form of pain relief for labour, what's known as the "gold standard".  Dr Simon Jones, Consultant Obstetric Anaesthetist

What is an epidural for pregnancy?

An epidural is given as an injection into the 'epidural space' in the spine. Epidurals stop you from experiencing pain in labour. Once they have given you the anaesthetic and painkillers, your anaesthetist will leave a small plastic tube (catheter) inside your back. This is so that the medicine can be "topped up", when necessary.

Epidurals are considered the most effective type of pain relief for labour, according to studies.

Some evidence suggests that epidurals for pregnancy can increase the length of labour and make it more likely that you will need an assisted birth. Assisted birth means using forceps (large metal 'spoons') or ventouse (suction cup) to help you birth your baby.

Dr Simon Jones, a consultant anaesthetist, told us "epidurals work on the pain channels in the spinal cord and central nervous system. We use a combination of anaesthetic and painkillers (analgesic) in epidurals."

Are epidurals painful?

A lot of women are worried about getting an epidural for pregnancy and how much it might hurt. It's normal to feel worried about a medical procedure you've never had before.

The good news is that your anaesthetist will numb the area before they insert the needle. The procedure to numb your back ready for the epidural might feel a little uncomfortable. Some women feel a stinging or burning sensation. However, the initial anaesthetic used will work quite quickly to stop you from experiencing any pain when the epidural needle and catheter is placed.

In some cases, the insertion of the epidural needle can cause a sharp, "shock" feeling. This doesn't happen to everyone but can be surprising. It happens when the needle hits a nerve. It is momentary but quite intense.

How long is an epidural needle?

It can sound scary, but an epidural needle is longer than the ones used for vaccinations. The needle is also wider than other hypodermic needles, as it is used to insert the plastic catheter.

The sizes of needles used for epidurals vary. Medical guidance suggests the most commonly used needles are 3.5 to 6 inches long. Your anaesthetist will choose which needle to use on the day, based on your body.

If you have a high BMI, you will be offered the chance to see an anaesthetist to discuss your birth plan. They can assess you in clinic and discuss your epidural for pregnancy. Your anaesthetist might need to use a slightly longer needle to reach the 'epidural space', )(where the medication is injected), than in those with a lower BMI.

The catheter in your back will stay there until your baby is born. This is so that medication can be given to you throughout labour. You will also need a urinary catheter and an intravenous drip for fluids.


Epidural side effects

Epidural side effects vary from woman to woman. Some of them are more common and others are very rare. It's important to weigh up all the epidural side effects before you consent to the procedure.

1. Low blood pressure (hypotension)

Studies show that epidurals for pregnancy can lower your blood pressure, which can make you feel dizzy and sick. However, your blood pressure will be checked regularly throughout labour and after birth. If your blood pressure drops too low, your healthcare team can give you fluids and medications to make you feel better quickly.

According to the Epidural Info Card by the Obstetric Anaesthetists' Association (OAA), 1 in every 50 women will have a significant drop in blood pressure.

2. Difficulty having a wee

As an epidural numbs your lower body, you won't be able to walk to the toilet. When you opt for an epidural, a nurse will put a urinary catheter into your bladder, through your urethra. This will direct urine into a bag next to your bed. The amount of urine will be monitored to make enough is coming out. Sometimes, after an epidural, some women might struggle to feel when they need to urinate. Usually, this effect wears off quickly.

A study by BMC Pregnancy Childbirth shows that in some rare cases,  epidurals can cause postpartum urinary retention. This means women sometimes struggle to empty their bladders (urinate).

3. Severe headache

Considered uncommon for the majority of epidurals (around 1/100 cases), some people will have a severe headache after an epidural. This is known as a "post-dural puncture" headache (PDPH). It is caused by a puncture to the dural sac, which contains fluid within the spine. This results in a leak of fluid, which can cause a very painful headache. However, this will usually get better over a few days.

If you have a PDPH, seek help from your midwife or GP. More about PDPH and treatment is available from the Obstetric Anaesthetists Association in their leaflet.

4. Ineffective pain relief

In a small number of women, the epidural does not work properly. Sometimes you might need the epidural to be repeated. You may be offered other types of pain relief in labour. This happens in 1 out of every 8 women according to the Epidural Info Card, Obstetric Anaesthetists' Association (OAA)

Other side effects include:

  • Temporary drowsiness
  • Feeling itchy
  • Nausea

In extremely rare cases, some women might experience severe injuries. A study published in the British Journal of Anaesthesia suggests an incidence rate of around 1.8 per 100,000 cases. This is so rare that it's not something that many anaesthetists have any experience of.

Speak to your midwife about your birth plan if the chance of rare side effects is causing you anxiety.

How long does an epidural last?

It takes about 20 minutes for an epidural to begin working and it will last for the entirety of your labour. This is because the epidural catheter stays in your back the entire time. An epidural ensures continual pain relief. If you decide you would like to stop receiving epidural drugs, it can be removed quickly.

There isn't much evidence on exactly how long epidurals last after removal. The effects of an epidural can vary for everyone, depending on how long you have been in labour and which drugs were used. Recovery from an epidural also depends on how long you've been receiving anaesthetic and painkillers.

According to the NHS, you will usually start to regain feeling in your body within a few hours once it is removed. You must not drive for at least 24 hours after an epidural.

At what stage is an epidural given?

Usually, doctors recommend you are not given an epidural until you are in "active" labour. The NHS definition of active labour is when your cervix is around 3-4cm dilated.

Some studies, including this 2021 research, suggest that having an epidural before you are 6cm dilated can increase the length of your labour.

Dr Simon Jones, Consultant Anaesthetist in Obstetrics recommends asking for an epidural early. He says "A epidural is more likely to be effective when you're not really struggling with the pain. Early is better, so if you do want an epidural, put it in your birth plan. Ask your midwife about pain relief as soon as you arrive at the labour and delivery suite."

How many cm is too late for an epidural?

Though it's recommended that you ask for an epidural early, that doesn't mean you can't have one later in labour. Some women might start labour feeling that they don't want an epidural, but then change their mind. There's no shame in changing your birth plan, especially if labour has been very long and tiring.

Consultant Anaesthetist Dr Simon Jones confirms "it's never really too late to give an epidural, unless the baby is arriving." He explains, "what's important is having the time to establish an epidural before the baby arrives. Otherwise, you get all the risk of the epidural, for none of the benefit. The other thing to consider is whether you can sit still while we safely provide the epidural. This is far harder to do if you are in advanced labour."

Can you feel the baby coming out with an epidural?

Some women worry that an epidural will stop them from connecting with their labour. Whether or not you will be able to feel the baby coming out with an epidural  for pregnancy depends on various factors, including

  • How long the epidural has been in place
  • When you received the epidural (early or late in labour)
  • How effective the epidural is for you

Some women will not feel anything after an epidural, whereas others will still feel the pressure of contractions.

Is an epidural right for me?

It's important to let your healthcare team know what you want from an epidural for pregnancy. Some women will want total numbness, so they can feel as little of the pain and discomfort as possible. Others may want to know that they will feel more when it's time to push.

Discussing your pain relief threshold and what you expect from labour with your midwife will help you decide whether an epidural is right for you. You can change your mind and accept an epidural, or go into labour and decide you don't want one. The decision on pain relief in labour is always up to you.

Related video: Old wives' tales for predicting the sex of your baby 

Tannice Hemming
Maternity and family writer

Tannice Hemming has worked alongside her local NHS in Kent and Medway since she became a parent and is now a mum of three. As a Maternity Voices Partnership Chair, she bridged the gap between service users (birthing women and people, plus their families) and clinicians, to co-produce improvements in Maternity care. She has also worked as a breastfeeding peer supporter. After founding the Keep Kent Breastfeeding campaign, she regularly appears on KMTV, giving her views and advice on subjects as varied as vaccinations, infant feeding and current affairs affecting families. Two of her proudest achievements include Co-authoring Health Education England’s E-learning on Trauma Informed Care and the Kent and Medway Bump, Birth and Beyond maternity website.